Bank of locking switch-keys.



AE. R. CORWIN & (LA. BALS. l v BANK or" LooKINe s'wl'ron rms.

Arrmumlbnrunnnmae, 1mm.v A

941,763. Patented Nov. 3o,19o9.

0 o o o o 17 f i? f uff l l. 6

l oo oo oo o@ :Iso oo la zyf ELMEB 1a. coRWYIN AND CHARLES A. BALS,

TIGN F ILLINOIS. f

To all whom it may concern:y

Be it known tlmtvu'e, ELMnn R. Conwln and CHARLES A. BALS, both citizensof the pro United States of America and residents of Chicago, Cookcounty, llinois, have invented a new and useful Bank of LockingSwitch-Keys, of which the followin is a specification, reference beingrhad to t e accom )anying drawings, illustrating same.

"j This present invention is an 'improvement on our United StatesLetters'v Patent No. 902,275, issued October 27, 1908.

1 Our invention relates tobanks of locking switch keys of thepush-.button t pe, the princi al objectsof our invention 'eing to provi'e improved' means for mounting such a bank of switch keys, to provide animproved casing for suoli a bank of keys, to

ide improvedmeans for connecting electrica conductors with the keys, toprovide improved means for controlling the switch contacts of thevarious keys of abank in intercommunicating or party-line telephonesystems, and `to provide improved means for releasing the various `keysof a bank by the depression of one of the keys.

Other objects will be apparent from the following specification. j i

In the accompanying drawings illustrating the preferred -form of o urinvention, Figurel is a side'elevation of a interior construction oft-heapparatus; Fig..

2 is an end elevation of the bank of locking switch keys shownffin`Fig-.1, with the inclosing casing shown in vertical cross-section toshow the interior construction of the I apparatusgand Fig. 3 is avertical crosssect1onal view of thebank of keys shown in F1os. 1 and, 2,takcnnnhne m of Fig. 1.

' o iike characters refer to like parts in the several figures.

In the drawings, 1 1 'represent a plurality :of push-buttons, euchbeingI connected by a stem 2 with a plungerI 3 which is adapted andarranged to operate" and control a set of switch springs et, 5, 6, 7 and8. In the sets of switch springs shown in Fig. 3 the springs of each setare all out of contact with cach other 'when thepush-button 1 is raised,thc depression of the pushbutton 1 causing the p unger 3 to engage theswitchd aF-CHICAGO, fLLINoIs, ASSIGNORS T'o ooitwmTnLnPnoNnmANUFAo'rUmNG COMPANY, or CHICAGO, ILLINoIs, A consona- BANKOli? LOCKING SWITCH-KEYS.

specification mi Letters Patent. Application illed January 29, 1909.Serial No. 474,968.A

bank of the improved locking switch-keys, with a perf ratentea Nov.30,1909.

springsit and 7 and thereb cause springs 4, :'rnnct t3' to contact cachot ier, and spring 7 to contact spring 8. lt will readily be understood,however, that the switch springs .(3 and 7 of each set may control anycombination of springs ns desired.

rlhe various sets of switch slirings are ,mounted on u plurality oluu'nlnting bars 9 9 preferably as shown, the mounting bars 9" 9 beingheld in place by a pair of end plates -10 10 as shown in l. `ig. 1. Aplurality of coil springs 11 11 act on the respective plungcrs 3. 3 toraise the latter and the respective push-buttons 1 1 whcnt'hcy are vrevleased.-

The end plates'10 10 are suitably secured to the top plate 12 whichserves as :n.guide for the various stems 2 2. rlheend 'plates 10 10 maybe also mounted to a mounting base 13 as shown in Fig. 1, to securelymount the bank of keys as a whole in place.; The cover or casing 14 isplaced over the bank ofkeys as shown? in Fig. 1 and is securely mountedto the .top plate 12 by screws 15 15 so that the cover 14 may be readilyremoved from the bank of keys when it'is desired to have access to theapparatu'swithin the cover 111. On, one of the end plates 10 10 issecured a strip of insulating material 1Gcarrying a plurality'ofterminal strips 17 17 vadapted to accommodate lconductors leading fromthe various switch sprin 's of the bank of keys and also conductorsceding to the bank of keys from the exterior of thc casing 14 throughopenings 18 18 in the ends of the casing 141. It, willbe readily seenthat this strip 16 with its terminal portions v 17 17 )rovidcs a greatlyimproved arrangeconductors.

The end plates 10 10 carry a pair of side bars 19 19 in notches therein,as shown in the drawings, these side bars 19 19 being held togetller bya plurality of cross bars 20 20. 'lhc side bars 19 19 carry another seto't'cross bars 21 21 adapted to engage notches 22 22 in the stemportions 2 2 as shown. o Each et the stem portions 2 2 is provided witha pair ot error..

notches 22'22 therein for the reception of a cross bar 21, the pair ofnotches'22 22 in each stem portion 2 being beveled on their upper facesso ythat .the depressionotE the corresponding push-button operates theside bars 19 19 and the cross bars 20 20 21. 21

a unit, end'wise, so as to release any of the other keys which iuay havebeen previously depressed. '.l`he beveled surface on each of the uppernotches in the stein portions i i 2 is tor the purpose. of causing therelease ot' the -va'rious keys ot the bank by a furtlicr depression otany of the push-buttonsl l 1, past locking position, when nioi'e vthanone of the keys, or all of. the keys. are loeked iin locking position,that is, in the position jection to such banks of locking keys, by pro-Viding the iipperbeveled notches on the various stems 2 2 for thepurpose stated. The

*side bars 19 19 carry still another cross bar 2t; against which a' leafspring 24 bears to operate the side bar unit 19 1t) 20 20 and 2l 2,1V asa whole, endwise, to cause the cross bars 2t 21 tOengage the variousnotches 22 22 of the stems 2 2. The leaf spring 2t is carried by'oiic oft-he end plates 10 preferably as shown, the end plate l0 being providedvwith an adjustment screw 25 for regu lating the tension of the spring 24against the cross bar 23,

Each of the pliingers 3 3 and the notches 22 22,.:issociatcd therewith,are constructed so that when any of the push-buttons l 1 isdepressedfroin normal position, .itwill cause the release of any of the)fish-buttons which mayiliave bcen,previoiisly depressed to lockingposition, before it lcauses the switch springs 6 ain'd 7 thereof toswitch any When,

of the contacts of its set of switch springs.

This is for the purpose of clearing the telephone eircuit ot' otherconnections, in an intercoinninnicating or party-line telephone system,helore the telephone is connected with t e circuit leading to the keywhich is being teicoinmiinicat in g telephone systems.

any ot' the push buttons l l is depressed to locking position, that is,to the position in' which its cross bar 21 rests in the iip'pervnotch'i'. of the.'kgy, the switch springs (5 and 7 are engaged by theenlarged portion 3 of the plunger as td cause springs 6 and 7 to engagespringst') and8 respectively, spring 4 being` still out of contact withsprintr 5. Now a -l'iirtherdepression` ot'ithe puslrbut.-

i ton, that is, past thc ,locking position,.causes the switch spring (ito engage the upper beveled portion 26 ofthe plunger and thereby causethe spring 5- .to engage the spring 1,

In keys heretofore made it was possidistributing strip and havinganfopfening positionreleases any vofthe other keys whicliwithoutoperating the switch spring 7 farther.v This construction gives asmooth, easy action to the push-buttons. The eonv tacts t3 5 and 7 S aregenerallyithe talkingcircuit contacts in an intercomiiiunicatingtelephone system, the contact 5 t being a. ringing contact. s 'l`liebank otl keys is provided with one push-button 2 which is connectedwitha stein 2S haring a single. long beveled notch :9 therein as showniii l"ig.1. The plunger :itt-on this stein 2S is so constructed that. it

switches its switch contacts before it releases anyo't thepush-buttons l'1 which 'I may have been previouslydepressed. This 30 isft'or thepurpose ot holding a trunk line iii an iutereoininuiiicating telephonesys-` teni. while a party called Lby' the attendant;` answers anincoming triuik all;` the key 2T establishing'a bridge i'icrosstheincoming common-batter i trunk when depressed, hetore theattendantstelephone disconnected from the .ti-link, t0 avoid' givingthe4 operator at. the ,common-battery elxchangea` disconnect signal.buehY a. construction greatly improves th'c `handling of ineomi'iivtriiiilecalls from a conin'ion-bstttery telef.

phone system to an intercoinmunicating telephone systein. It. willreadily be seen` that the key 27 is not-locked indepresstades'4position, because .it has but Iasingle notchl 2S) iii the sten )ortion28.

We do not. wish to limit this invention to all of the exact details ofconstruction` hert-in shown, as various modifications inisaine may hemade without departing from `thc scope of the 'appendedclaims., i

W hat we elaini as our invention is: y

l. A bank of switehkeysroinprisinga suitable li'ainea'nd apluralityzof;ipushfbiits. ton switches, adapted to be mounted t.toilsuitable base, a `distribiitinf"stri l L ing-terminals thereoncarriet'by tie 4 d frame whereby conductors i leading ff-froni the saidswitches..may',he connected-with external conductors leading to theLbank of keys,-and la` removable easing carried by the bank ot' keysuiidattachedthereto, the said casing iiiclosing thesaidlsivit'che` '115 lllieiethroiiiih A for" accommodating ternal condiictors vleading tothelist strip. .f v .y 2. A bank of switch keys having a lur'al-f' ityof plungersand switches ada te .'tobe 120 operator-l thereby,l means forloc g'st nfnev fof the phingers in depressed position, means, l

associated with at-4 least one of the plunger-s whereby the .depressionthereojf'from normalhv niay have been lockedin depressed position," A I'before the p-linigcr' which vis being depressed i Switches its.switchcontacts at least one of'y the phingers being constructed' sothat it switches its switchcontacts before causing i the release of anyof the other plungers which may have been locked in depressed position.Y 3.,A bank of locking switch keys comprising a plurality of pl angersand switches adapted to be operated thereby, means for l locking thevarious keys in depressedpolsition, means associated With each of the,plungers whereby the depression thereof releases any of the otherplungers which ma1 have been locked in depressed position, z some of theplungers being constructed so as to cause the release of the otherplungers, when depressed, before switchingr their switch contacts, andat least one of the: plunger-s being constructed so as to switch i itsswitch contacts, when depressed, before causing the release 'of theother plungers.

4. A bank of switch keys having a plurality of plungers and switchesadapted to be i operated thereby, means for lockingr soule of theplunger-s in depressed position, means whereby the depression of atvleast one ot' the plungers causes the release of the otherpluugers whichmayv have been looked in (.iellressed position, and `means assm-iatedwit-h at least one of the plunger-s whereby the depression thereof fromnormal position switches its switch contacts before causingthereleaslevof any ofthe. other plungers which may have been locked indepressed position.

.\s inventors of the foregoing, we hereunto subscribe our names, this26th day of January, 1900.

IlLMlll-i i. CORVN.

AN. ]5;\l1s.

Fmannalcn R. Palmi-:a 1 FRANK RYAN.

